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Directive and Steerable Radiation Pattern using SASPA Array

This work examines the ability of a special type of smart antenna array known as Switched Active Switched Parasitic Antenna (SASPA) to produce a directive and electronically steerable radiation pattern. The SASPA array consists of antenna elements that are switchable between active and parasitic states by using P-Intrinsic-N (PIN) diodes. The active element is the element that is supplied by the radio frequency while short-circuiting the terminals of an element in the array results in a parasitic element. Due to the strong mutual coupling between the elements, a directional radiation pattern with high gain and a small beamwidth can be produced with only one active element operating at a time. By changing the parasitic state to the active state sequentially for all elements, the directed radiation pattern can be easily rotated. The antenna array structure used in this work is the uniform circular array (UCA) to achieve symmetrical radiation patterns and full coverage of the entire azimuth plane. Also, a novel method for reducing the mutual coupling effect in SASPA arrays is proposed in this work. By using this method, some parameters of the generated SASPA’s radiation pattern can be controlled. The simulated results obtained from this work depict that an N-element SASPA-UCA produces N-symmetrical, switchable, and steerable radiation patterns with high gain, small beamwidth, and a high Front-to-Back (F/B) ratio. Also, the results show that further improvements in these parameters can be achieved by increasing the number of elements in the array. Additional simulations demonstrate that by including decaying function weight in each element's circuitry, the mutual coupling between the components of the SASPA-UCA array can be minimized. The aforementioned parameters can then be efficiently modified using this mutual coupling reduction.

 

 

 

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Publication Date
Fri Jan 01 2016
Journal Name
International Journal Of Advanced Computer Science And Applications
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Publication Date
Sat Feb 09 2019
Journal Name
Journal Of The College Of Education For Women
Comparative Study of Image Denoising Using Wavelet Transforms and Optimal Threshold and Neighbouring Window

NeighShrink is an efficient image denoising algorithm based on the discrete wavelet
transform (DWT). Its disadvantage is to use a suboptimal universal threshold and identical
neighbouring window size in all wavelet subbands. Dengwen and Wengang proposed an
improved method, which can determine an optimal threshold and neighbouring window size
for every subband by the Stein’s unbiased risk estimate (SURE). Its denoising performance is
considerably superior to NeighShrink and also outperforms SURE-LET, which is an up-todate
denoising algorithm based on the SURE. In this paper different wavelet transform
families are used with this improved method, the results show that Haar wavelet has the
lowest performance among

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Publication Date
Tue Aug 01 2023
Journal Name
Advances In Mechanical Engineering
Using a spherical inverted pendulum and statokinesigram for modeling and evaluating quiet standing posture

This paper proposes a new approach to model and analyze erect posture, based on a spherical inverted pendulum which is used to mimic the body posture. The pendulum oscillates in two directions, [Formula: see text] and [Formula: see text], from which the mathematical model was derived and two torque components in oscillation directions were introduced. They are estimated using stabilometric data acquired by a foot pressure mapping system. The model was quantitatively investigated using data from 19 participants, who were first were classified into three groups, according to the foot arch-index. Stabilometric data were then collected and fed into the model to estimate the torque’s components. The components were statistically proce

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Publication Date
Mon May 14 2018
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Detection and Detoxification of Aflatoxin B1 from Fish Feedstuff Using Microwave and Ozone Gas

    The current study was designed to investigate the occurrence of aflatoxin B1 in thirty two samples of fish feedstuff were collected randomly from some Iraqi local markets using ELISA technique. Aflatoxin B1 was detected in thirty samples and the concentration of toxin ranged from 50 ppb to 1000 ppb.  

   Microwave and ozone were used for detoxification of aflatoxin B1 from sample with highest concentration (1000 ppb), two degree of temperature and two times (50°C and 100°C for 5 minute and 10 minute to each degree) of microwave, also two doses and two times (2 g and 4 g for 5 minute and 10 minute to each dose) of ozone gas were used.

   Degradation of aflatoxin B1 by

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Publication Date
Mon Jan 01 2024
Journal Name
Baghdad Science Journal
Water Treatment Using Zinc Nanoparticles and Apricot Plant Extracts from Organic and Inorganic Pollution

 

The apricot plant was washed, dried, and powdered after harvesting to produce a fine powder that was used in water treatment. created an alcoholic extract from the apricot plant using ethanol, which was then analysed using GC-MS, Fourier transform infrared spectroscopy, and ultraviolet-visible spectroscopy to identify the active components. Zinc nanoparticles were created using an alcoholic extract. FTIR, UV-Vis, SEM, EDX, and TEM are used to characterize zinc nanoparticles. Using a continuous processing procedure, zinc nanoparticles with apricot extract and powder were employed to clean polluted water. Firstly, 2 g of zinc nanoparticles were used with 20 ml of polluted water, and the results were Tetra 44% and Levo 32%; after

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Publication Date
Mon Jun 01 2020
Journal Name
Al-khwarizmi Engineering Journal
Analysis of Different Hand and Finger Grip Patterns using Surface Electromyography and Hand Dynamometry

Recording an Electromyogram (EMG) signal is essential for diagnostic procedures like muscle health assessment and motor neurons control. The EMG signals have been used as a source of control for powered prosthetics to support people to accomplish their activities of daily living (ADLs). This work deals with studying different types of hand grips and finding their relationship with EMG activity. Five subjects carried out four functional movements (fine pinch, tripod grip and grip with the middle and thumb finger, as well as the power grip). Hand dynamometer has been used to record the EMG activity from three muscles namely; Flexor Carpi Radialis (FCR), Flexor Digitorum Superficialis (FDS), and Abductor Pollicis Brevis (ABP) with different

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Publication Date
Sun Jan 30 2022
Journal Name
Iraqi Journal Of Science
Human Activity Recognition using Smartwatch and Smartphone: A Review on Methods, Applications, and Challenges

     Recently, Human Activity Recognition (HAR) has been a popular research field due to wide spread of sensor devices. Embedded sensors in smartwatch and smartphone enabled applications to use sensors in activity recognition with challenges for example, support of elderly’s daily life . In the aim of recognizing and analyzing human activity many approaches have been implemented in researches.  Most articles published on human activity recognition used a multi -sensors based methods where a number of sensors were tied on different positions on a human body which are not suitable for many users. Currently, a smartphone and smart watch device combine different types of sensors which present a new area for analysi

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Publication Date
Sun Jul 31 2022
Journal Name
Iraqi Journal Of Science
A Comparative Study Using DCT, Delta Modulation, and Double Shift Coding for Compressing Electroencephalogram Data

      Storing, transferring, and processing high-dimensional electroencephalogram (EGG) signals is a critical challenge. The goal of EEG compression is to remove redundant data in EEG signals. Medical signals like EEG must be of high quality for medical diagnosis. This paper uses a compression system with near-zero Mean Squared Error (MSE) based on Discrete Cosine Transform (DCT) and double shift coding for fast and efficient EEG data compression. This paper investigates and compares the use or non-use of delta modulation, which is applied to the transformed and quantized input signal. Double shift coding is applied after mapping the output to positive as a final step. The system performance is tested using EEG data files from the C

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Publication Date
Fri Nov 24 2023
Journal Name
Iraqi Journal Of Science
Normal and Reverse Flow Injection- Spectrophotometric Determination of Vancomycin Hydrochloride in Pharmaceutical Preparations Using 2, 4-Dinitrophenylhydrazine

Simple and sensitive batch and flow injection methods (normal and reverse flow injection analysis (nFIA and rFIA)) for spectrophotometric determination of vancomycin hydrochloride (VHC) in pharmaceutical preparations were proposed and optimized. Both methods are based on the oxidative - coupling reaction between vancomycin hydrochloride and 2,4-Dinitrophenylhydrazine (DNPH) in the presence of sodium periodate in alkaline medium to form a yellow water-soluble product that is stable and has a maximum absorption at 461 nm. Beer’s law was obeyed over the range of 1- 40, 0.5-120 and 0.5-150 μg.mL-1; the limits of detection were 0.537, 0.0823 and 0.233 μg.mL-1 for batch, normal and reverse flow injection methods respectively. The sampling

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Publication Date
Wed Feb 08 2023
Journal Name
Iraqi Journal Of Science
Delineation of K-3 Cavity Using 2D Imaging Resistivity Technique in Haditha Area (Western Iraq)

The 2D imaging survey was conducted across an unknown K- 3 cavity that is located in Haditha area-Western Iraq.2D measurements are collected along two intercrossing traverses above the cavity with 105m length of each one. Dipole-dipole array is performed with n-factor of 6 and a-spacing equals to 5m. The inverse models of 2D imaging technique showed clearly that the resistivity contrast between the anomalous part of cavity and background resistivity of rocks is about 800:100 Ωm .In addition, the invers models showed that the depth from ground surface to the upper roof of cavity approximately equals to 11m near the cavity operator. So, the K-3 cavity is well defined from 2D imaging with Dipole –dipole array in comparison with the actua

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